Question

Question #a9b5d

Answer 1

An ion is an atom or group of atoms with a charge. If the ion is an atom find the protons and neutrons in the normal fashion and then adjust the number of electrons according to the charge.

Explanation:

Take Bromine as an example. `Br_35^80`
35 the atomic number always gives the number of protons.

protons and neutrons equals the atomic mass so

`35 + n = 80` subtract 35 from the total mass to find the neutrons

`35 -35 + n = 80 -35 = 45`

`n = 45` neutrons equals 45

The number of electrons equals the number of protons in a neutral atom. so the number of electrons also equals the atomic number in an atom before it becomes an ion.

Remember that electrons are negative so a negative ion has extra electrons and a positive ion has lost electrons.

So Bromine starts with -35 electrons + -1 electron = - 36 electrons.